[Does knowledge hurt?]

The rate of production of medical knowledge is high and increasing, and medical practitioners find it hard to keep up. Still, production of new knowledge is normally considered to be unambiguously desirable. This paper is a philosophical reflection upon this assumption of desirability. It is noted that the health sector appears to be subject to the law of diminishing returns; this implies that more doctors and more medical technology may at some level do more harm than good. We argue that Bacon's legitimization of knowledge (knowledge is power) is less forceful in the face of biological and psychosomatic complexity. Medical research may lead to unintended harm through at least two mechanisms. First, biomedical knowledge is reified through the introduction of new medical technology whose effects are not fully known, and may lead to uncontrollable adverse effects on a clinical and societal level. Second, exaggerated attention paid to the production and implementation of biomedical factual knowledge may prevent the development and teaching of personal clinical skills, including phronesis, the individual judgemental powers that enable us to judge which goals are worth striving for, and which are not.